1. Field of the Invention
The present invention relates generally to valves, and in particular to a valve system with full flow and multiple pressure regulating positions.
2. Description of the Related Art
Various valve systems have heretofore been proposed for controlling the flow of different types of fluids. Such valve systems can be actuated manually or automatically, and typically have open and closed positions for respectively permitting and blocking fluid flow therethrough.
Previous valve systems have utilized fluid pressure differentials to control their opening and closing movements. For example, pressure regulating valves are available with valve members which are controlled in this manner. Such valves are retained in their closed positions by fluidically connecting control and inlet chambers thereof whereby greater areas of their valve members are exposed to fluid pressures in the inlet chambers. The valve opening sequence in such a system can be initiated by opening the control chamber to the valve outlet side, thus lowering the pressure within the control chamber whereby the valve member is moved to its open position by greater fluid pressure in the inlet chamber.
It is often desirable to regulate the outlet pressure of a system for dispensing water or other liquids so that consistent pressure is maintained for use in a system located downstream from a pressure regulating valve system. Multiple regulated pressures are sometimes preferred. Different water pressures may be called for by various conditions. For example, an irrigation system may utilize different water pressures for accommodating different sprinkler networks and for providing irrigation coverage over different areas of different sizes. Another example of an installation wherein multiple pressure regulating valves could be utilized is in a vehicle washing facility where different water pressures may be required for, e.g., the wash, rinse and wax cycles.
Matching the outlet pressure to the requirements for a particular task can be important for purposes of water conservation. In many parts of the country potable water supplies are in scare supply and subject to ever-increasing demands. This situation has resulted in strict water usage controls and rationing in some parts of the country, limitations on permits for new water hookups, and higher water rates. Efficient utilization of water resources has thus assumed greater importance in many areas, and has become an important factor in controlling costs among businesses which utilize large quantities of water, e.g., for irrigation, washing, etc.
Valve systems have heretofore been available which provided for flow rate adjustments. For example, valve assembly handles have been provided which can be turned through ranges of motion to vary the outputs. Also, valve systems have been provided with controls which utilize relays, solenoids and the like for remote actuation. Pressure regulating valve systems have also been available which have full flow and pressure regulated positions. However, heretofore there has not been available a variable pressure regulating valve system with the advantages and features of the present invention.